The following is a summary of “Application of Intraoperative Structured Light Scanning to enable Post-operative Evaluation of Digital and 3D-printed Penile Models,” published in the May 2024 issue of Pediatrics by Huang et al.

The assessment of penile phenotype in hypospadias traditionally relies on visual or manual methods, such as using a ruler or goniometer, which are often imprecise, inconsistent across different raters, and incapable of retrospective evaluation post-surgery. This study aims to evaluate the precision and reliability of penile dimensions derived from digital and three-dimensional (3D) printed models created using intraoperative structured light scanning (SLS) during primary pediatric penile procedures. In this prospective study (IRB #20-000143), boys aged 1 month to 6 years undergoing first- or single-stage penile surgery at a single institution were enrolled. Intraoperative measurements were taken with a ruler after placing a stay suture under consistent manual tension. 

Concurrently, a digital 3D model was generated using an Artec Space Spider scanner and Artec Studio 13 software before the penile repositioning. Post-surgery, two raters conducted ten digital measurements on each generated model using Autodesk Fusion 360, and the models were subsequently 3D printed for further measurement. Using a ruler, two different raters then performed ten manual measurements of each 3D-printed model. The agreement between and within raters was assessed using a one-way random effect intraclass correlation coefficient (ICC), with analyses conducted in R version 4.2.

Results from six scans (four hypospadias and two circumcisions) indicated that intra-rater assessments of digital measurements demonstrated excellent precision. Manual measurements of 3D printed models showed excellent reliability for glans width and penile length but varied from poor to good for glans height. Inter-rater reliability was good to excellent for glans width (0.77 to 0.95) and good for penile length (0.71 to 0.88) but poor for glans height (0 to 0.14). Training on the glans’ height location subsequently improved the precision and repeatability of both manual and digital measurements. The study concludes that digital measurement of OR-derived 3D models provides excellent repeatability for each rater and improves inter-rater reliability compared to manual measurements alone. This indicates the potential for SLS as an innovative modality for creating digital 3D models, enhancing phenotypic analysis for both research and educational purposes. 

Future work will focus on further developing digital measurement methods to ensure consistency across raters for additional quantitative parameters and evaluating this technology in pre-operative environments for surgical planning.

Source: sciencedirect.com/science/article/pii/S1477513124002699